Draft regulator and scrubber



July 24, 1962 T. J. KEENAN, JR 4 DRAFT REGULATOR AND SCRUBBER FiledApril 10, 1959 2 Sheets-Sheet 1 5| INVENTOR.

Thomas J. Keenan,Jr. BY

July 24, 1962 T. J. KEENAN, JR 3,045,990

DRAFT REGULATOR AND SCRUBBER Filed April 10, 1959 V 2 Sheets-Sheet 2 Flg. 4 7 IP00 M 000:! I 1 |o'9 l09/ r we I I y M I C? '1- 5 70E?- II 1i JFig. 5.

INVENTOR. Thomas J. Keenamdr.

BY I lW/A-aj/W/ United States Patent Ohhce Bfidfifidh Patented July 24,1932 3,045,990 DRAFT REGULATGR AND SCRUBBER Thomas J. Keenan, lira, 4350Park Blvd, (laidand 2, Qalif. Filed Apr. it), 1959, Ser. No. 365,576 3(El. Zeb-J29) This invention relates to a draft regulator and scrubber.

More particularly this invention relates to new and useful improvementsto draft controlling devices and to related controls for the flow ofgases and vapors. It is adapted, more especially, for controlling andregulating flue gases and vapors from boilers, furnaces, ovens, retort-sand similar equipment or appurtenances, although it is adaptable as themeans for use as a collector and precipitator of suspended particles ingas and vapors. This invention is novel and unusual when compared toother draft regulators and controls in many respects, especially in itsdamper effect, its accommodation as to various capacities, itsreversibility of operation and to its wide range of uses.

A principal object of this invention is to provide a new draft controlsmog eliminator and spark arrester by the provision of a circular rim ofWater adjacent the mouth of the smoke stack and a cap for the smokestack supported by floats on the water in such a way that the cap can beregulated at controlled spaced distances with respect to the mouth ofthe stack simply by changing the level of water within the circular rim.

Another object of this device is that it affords the means by suchretardation and control of the gases and vapors; to permit and assist inobtaining the proper chemical reaction or the complete combustion of thefuel and thereby greatly reducing the amount of soot or suspendedparticles in the effluent gases and vapors; to obtain an evendistribution of the heat within the confines of the working chamber and;to obtain a resultant higher efficiency with heat interchangers, eitherin the absorption or extraction of heat operations.

A feature and advantage of this invention is that the cap for the stackis formed with a depending rim which is adapted to extend downwardlybeyond the mouth of the stack so that smoke emitted from the stack isforced to pass downwardly between the cap and the outer wall of thestack and is guided to pass directly over the water. Heavy materialstend to drop into the water and much of the solid matter is removed fromthe smoke by the passage of the smoke closely over the surface of thewater.

Another object of this invention is the provision of the depending sidewall of the cap being arranged in a fixed and evenly spaced relationrelative to the surface of the Water regardless of the spacing of thecap relative to the top of the mouth of the smoke stack. By this meansthe resistance offered by virtue of the cap relative to the mouth of thestack can be increased or decreased by raising and lowering of the waterlevel while maintaining a constant resistance to smoke flow between thebottom rim of the cap and the surface of the water.

A feature and advantage of this control is that the force or pressureexerted against the stack to force the smoke downwardly over the watercan be varied by relatively positioning the cap in either the downwardor upward position.

A still further object of this invention is to form the water containerand the cap in oppositely facing relation so the rim of the cap extendscloser to the wall of the circular water container as the cap islowered. When the water is reduced to its minimum level within the watercontaining tank the cap is arranged to abut the top edge of the stack tocompletely shut off communication between the stack and atmosphere.

A feature and advantage of this invention is that a draft control isprovided by controlling the amount of water within the tank.

Another object of this invention is to provide means for minimizing theeffect of the cap by mechanical means which hold the cap atpredetermined elevated positions with respect to the stack and overcomecompletely the effect of the floating action of the cap on the water.

Another object of this invention is to provide means to support the capwith respect to a fixed point with sutficient flexibility so as to allowthe cap to register in substantially perpendicular alignment relative tothe mouth of the smoke stack.

A still further object of this invention is to provide a series ofstreams or sprays of water from the edge of the mouth of the stacktowards the side wall of the cap to scrub the smoke as it is emittedfrom the stack.

Another object of this invention is to provide an outer wall above thecap of the stack and water bath having a restricted outlet and in whichwater sprays: are arranged to clean the smoke as it travels from thewater bath and out through the restricted opening.

The device acts as a spark arrester. In the bonnet or cap the sparks intheir downward travel impinge upon water or liquid in the tank and aredeposited or collected in the tank. The sides of the tank are extendedabove the highest liquid or Water level in the tank to effect thispurpose.

The device is also a precipitator and a collector of fly ash, soot andsuspended particles in the gases and vapors, due mainly to the directionof travel of the gases and vapors in the bonnet or cap and the velocitycontrol factor. To assist in this performance a circular pipe line withspray holes or atomizing sprays attached thereto is placed at thedischarge end of the tank cylinder and also about one foot above the topliquid or water level and in the center of the space between the largestdiameter of the bonnet or cap and the side of the tank. A similar and anauxiliary spray line may be placed above the last described spray lineif necessary.

Other objects of the present invention will become apparent upon readingthe following specification and referring to the accompanying drawingsin which similar characters of reference represent corresponding partsin each of the several views.

In the drawings:

FIG. 1 is a cross-sectional view of the principal embodiment of theinvention showing the cap in one position in solid lines and in asubstantially more elevated position by dotted lines.

FIG. 2 is a fragmentary top plan cross-section taken at line 22 of FIG.2.

FIG. 3 is an enlarged fragmentary view of the swivel joint connectingthe cap to the body of the frame of the device.

FIG. 4 is a cross-sectional View of a modification of the invention.

FIG. 5 is a top plan view of FIG. 4.

In the embodiment of FIGS. 1, 2 and 3 the draft regulator and scrubberapparatus indicated generally at A is mounted on the upper portion of asmoke stack B.

Apparatus A comprises a. stack extension 15 and a water tank 16 mountedon the bottom portion of the stack extension to form a conical watertank or bath which completely surrounds the upper extension of thestack.

A cap generally indicated at C is mounted directly over the stackextension. Cap C is supported by a float Zil, floating in Water 25contained within tank 16, so as to position cap C above the mouth ofstack extension 15.

The device operates to widen or restrict the effective opening betweenthe stack and cap C by relatively raising and lowering the cap relativeto the mouth of the upper edge of the stack. The raising and lowering ofcap C is caused by changing the level of water within tank 16.

Cap C is formed of a top plate 28 and an annular side wall or flange 29which is attached to the rim of the top plate and depends outwardlytherefrom. Float 20 is connected to flange wall 29' by spacer members31. Spacer members 31 are rigidly attached to the top portion of float2t? and rigidly iaflixed by nuts 36 to brackets mounted on the insidewall of flange or wall 29.

The float is formed of a hollow annular member which completelycircumscribes stack extension 15 of stack B. The inner diameter of thefloat is sufficiently greater than the outer diameter of stack extension15 so as to allow completely spaced unimpeded vertical reciprocalmovement of the float relative to the stack extension.

Spacer members 31 are adjusted to support cap C so that all portions ofthe bottom edge 40 of wall 29 is a predetermined small equal distanceabove the surface 41 of water 25. The spacer members also allow cap C tomove upwardly and downwardly proportionately to the height of the waterin such a Way that at the low or mimimum water level the bottom of topplate 28 will abut the top edge or rim 45 of stack extension 15 so as tocause a complete fluid seal across the top of the smoke stack. When thewater rises to a higher level than the minimum, cap C is arranged toraise proportionately with the raise in the water level so as toincrease the spacing between stack rim 45 and the bottom of plate 28.

The upper edge of tank 16 is provided with an annular wall 48 whichextends upwardly substantially beyond the maximum upward positioning ofcap C. An X- shaped brace member 50 is mounted on the upper edge of wall48. The brace member comprises two intersecting beams 51 and 52 disposednormal to each other and each attached on the upper edge of wall 48 asat 53. The intersection of beams 51 and 52 is arranged in axialalignment with stack B.

A vertical bearing 55 is mounted at the intersection of the two beams inaxial alignment with the stack. Bearing 55 is arranged to carry a shaft59 for vertical reciprocal movement within bearing 55 on an axis axiallyaligned with stack B. The bottom end of shaft 59 is connected by aball-and-socket joint 6% to the top of flat plate 28 so as to allow forangular and pivotal movement of cap C relative to the shaft. Anelectrically actuated brake mechanism 62 is mounted on shaft 59 abovebearing 55 which is solenoid actuated by an electrical circuit (notshown) so as to controllably lock shaft 59 relative to bearing 55.

Water is supplied to tank 16 through a pipe 68 which communicates withan annular pipe 69 attached to the outer wall of the extension 15immediately under rim 45. Pipe 68 is arranged with a plurality of smallapertures through which water is emitted in a fine outward and downwardjet spray. Water is withdrawn from tank 16 by a drain line 71 and anoverflow line 72. The drain line connects to the bottom portion of tank16 as at 75 and the overflow line connects to an annular gutter 78located on wall 48.

The top of the apparatus is covered by a conical cover plate 80 having arestricted aperture 81 which is substantially the same diameter as stackB.

In operation water 25 is supplied to tank 16 so that the water levelreaches a predetermined level.

The spacer members 31 are affixed via nuts 36 in order to equalize thespacing between bottom edge 40 of wall 29 of cap C and the surface ofthe water so that the spacing of the cap above the water is equalthroughout the entire diameter of the cap wall.

Ball-tandsocket joint is sufliciently yieldable to allow the cap tofreely adjust in parallel or horizontal alignment with the water levelin the tank. There is thus exactly even openings between the cap and thewater on all sides of the cap.

When smoke is emitted from stack B the smoke is normally arranged topass from upper extension 15 over top edge 45, thence downwardly towardthe water, thence out the opening between bottom edge 4% and the surfaceof the water and thence upwardly out through the restricted mouth 81 ofthe top of the apparatus. As the smoke passes the surface of the waterhot sparks and heavy matter contact the water wherein much of the solidmaterial is withdrawn from the smoke by the water. The accumulation ofdebris in the water is withdrawn from tank 16 with the withdrawal of thewater through drain pipe 71.

Should it be desired to completely close off the stack, or to create adamper action the amount of water within tank 16 can be reducedsufficiently so that the bottom face of flat plate 28 abuts rim 45 ofthe stack. This completely closes off the top of the stack. An additionof water will raise the cap sufliciently so as to create an openingbetween rim 45 and top plate 28 which is directly proportionate to theamount of water added to the tank. It is to be noted that in all caseswhen the cap is supported by floating floats 20 the spacing betweenbottom edge 49 of side wall 29 remains in equal spaced relation to thesurface of the water.

An inverted conical deflector element 85 is mounted to depend downwardlyfrom the bottom surface of plate 28 and acts as a deflector element todirect smoke outwardly toward the outwardly depending walls 29.

Normally bearing 55 allows the cap to raise and lower with the increaseor decrease of water within tank 16. However, it may be desired to raisethe cap substantially above the top of the stack and to provide a widerspace between bottom edge 40 and water surface 41. To do this waterlevel 41 is raised to its upper limit either at or near gutter 78.Thereafter brake 62 is actuated so as to lock shaft 59 in place. Waterlevel 41 is then lowered to a desired minimum. Brake 62 therein holdsthe cap in an elevated position above the top of the stack completelyindpendent of the action of float 29. To again lower the cap so as tocause the cap to react with the Water level, brake 62 is merelyreleased.

Shaft 59 and bearings 55 function to align the cap in precise coaxialalignment relative to the axis of stack B so that the cap is alwaysaligned properly with rim 45.

Gutter 78 is arranged with a drain slightly below the upper level of rim45 so as to catch any overflow of water which may result from too muchwater being sup plied within tank 16 thus preventing any Water fromflowing into stack B.

The Wfi'tfif spray from pipe 68 is directed toward the inner face ofwall 29 so that the smoke passing from stack l3 must pass through thewater spray path through the apparatus.

The spray from pipe 63 effectively scrubs or removes the smoke particleswhich are capable of absorbing moisture and causes the particles tosettle out in water 25. Additional sprays of water may be connected to apipe on the inner wall 43 so as to cause the entire chamber defined bythe top wall 80 and side wall 48 with a mist or fine spray of water.Such a spray has the additional advantage of cleaning the smoke whichpasses through the apparatus.

A circulating system can be arranged so that the spray from pipe 90 andpipe 68 can continually be added to water 25 while an equal amount ofwater is withdrawn from drain pipe 71. This may be done by anelectrically controlled valve which may be actuated by a float mechanismgenerally indicated at 90.

In the embodiment shown in FIGS. 4 and 5 there is provided amodification of the invention in which a tank is mounted on a stackextension 101 and in which a cap 105 is mounted above the stackextension on floats 106. The structure of tank 1% and the cap and floatmechanism is identical to tank 16 and float mechanism 20 shown in theembodiment of FIG. 1.

The upper level of tank 1% stops at a level substantially coincident thetop edge 108 of stack extension 101.

Frame members 109 extend upwardly to a position substantially above thetop of cap mechanism 105 to form the support members for cross beam andbearing support members 115 which are identical to beams 51 and 52 shownin the embodiment of FIG. 1.

Support members 115 carry the identical mechanism for supporting andbraking the aligning shaft.

In this device it is to be noted that there is no cover extending abovethe top of tank 1% so that smoke passing from under cap 105 is free topass directly to atmosphere.

The drain line from tank 100 comprises two pipes 120 and 121 operated byvalves 123. The pipes are mounted one above the other with respect tothe level of water within the tank. By this means an average water levelcan be obtained at the height of the top water pipe 120 by using thispipe as an overflow pipe and the obttom pipe 121 can be used for furtherregulation purposes.

It is to be understood that for purposes of claim terminology the smokestack extension is considered to be equivalent to the upper portion ofthe stack itself.

The open type system is installed at the end of the pipe line or duct orchimney on the gas and vapor appliance.

The closed type system can be installed similar to the open type systemand it also can be installed at any intermediate point or points of thegas and vapor pipe line or duct. It also may be installed singly or itmay be installed in series or in multiples.

This device has an unusual feature which is its ability to re-establishpre'installation conditions within itself. To do so, the bonnet or capis raised to its highest position and set if so desired. This permitsthe accomplishment of this feature, for in this bonnet position there isno restriction as to area or velocity and there are no flowinterferences.

For gas and vapors heavily laden with suspended particles a filter orfiltering material is placed in the tank cylinder or inlet pipe for bothsystems. For the closed tank system a filter or filtering material mayalso be placed in the output pipe of the tank atop of the conicalportion of the tank.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity ofunderstanding, it is understood that certain changes and modificationsmay be practiced within the spirit of the invention as limited only bythe scope of the appended claims.

What is claimed is:

1. In a draft regulator for a vertical smoke stack of the type having atank forming an annular water bath around the mouth of the stack, a capmounted over the top of the stack and a float buoyantly supporting saidcap on the Water within said tank so that a variation in water levelwill change the effective spacing between the cap and the stack foregress of gases of combustion the improvement comprising, said cap beingformed in a closed deep truncated conical configuration forming a fiattop and an outwardly depending side wall overlying a substantial area ofwater adjacent the stack, said fioat being a buoyant ring of widerdiameter than said stack and mounted around said stack within the waterof said tank, spacer members connected to said float and extendingupwardly to said cap, holding said cap spaced above the stack with thelower edges of the side wall spaced closely above the Water level withinsaid tank, a support member rigidly mounted on said tank above said cap,a vertical bearing mounted on said support member in axial alignmentwith said stack, and an inflexible shaft vertically slidably supportedby said bearing and connected on its bottom extremity to the top portionof said cap, said bearing supporting said shaft for vertical movement inaxial alignment with said stack and being connected to the center ofsaid cap to maintain said cap and float in axial alignment relative tosaid stack.

2. A draft regulator according to claim 1 and wherein locking means areconnected to said bearing means to lock said shaft against movementrelative to said bearing means.

3. A draft regulator according to claim 1 and wherein an invertedconical deflection bafile is mounted on the underside of the flat top ofsaid cap with its apex in axial alignment with the center of the stack.

References Cited in the file of this patent UNITED STATES PATENTS819,074 Monroe May 1, 1906 881,735 Starrett Mar. 10, 1908 1,171,750 Poolet al. Feb. 15, 1916 2,862,354 Barnhart Dec. 2, 1958

